Conventional package-type power modules need gel encapsulation of semiconductor elements. A large number of assembly process steps and high parts cost are required for such power modules. Power modules having semiconductor elements transfer-molded are therefore being developed (see, for example, Patent Literature 1). A resin-molded semiconductor package needs to be fixed on a cooling device in order to be cooled, and a method of fixing such a semiconductor package by using screws or the like has been proposed (see, for example, Patent Literature 2).